In this commit we complexly revamp the process of restoring all channel
state back into memory after a restart. We’ll now properly do the
following: restore the pending “dangling” commit of the remote party
into the in-memory commitment chain, re-populate all active HTLC’s back
into their respective update logs with the proper indexes/counters, and
properly restore the current commitment of the remote party back in
memory.
This commit adds a new method to the updateLog which will be used when
restoring the state of a channel from disk after a restart. This new
method will add an entry to the updateLog without incrementing either
of the counters as the HTLC already comes pre populated with its
historical index.
With these new fields, we’ll be able to properly reconstruct the log
state after a restart, as each commitment will now note both the
current HTLC and log index.
In this commit we’ve extended the TestChannelStateTransition method to
exercise the new state transition related messages. This includes
ensuring that when we add a new dangling commitment, and then the
remote party revokes it, then the on-disk state is update accordingly.
In this commit, we update the CloseChannel method to respect the new
on-disk bucket based structure. Additionally, we now ensure that we
delete the new chainBucket.
In this commit, in addition to the renaming we’ve modified the behavior
of AdvanceCommitChainTail as follows: this method now will simply
atomically advance the commitment tail, set the new commitment to the
prior dangling commitment, and update the on-disk revocation log.
The macho expects the new revocation state to already be stored within
the channel. This method is to be called once the remote party revokes
their current commitment state.
In this commit, we add a new method: RemoteCommitChainTip. This method
allows callers to poll the database state to check if we have an
un-acked commitment for the remote party. If so, then it should be
retransmitted once a communication channel has been re-established with
the channel peer. This method will return ErrNoPendingCommit if we
don’t currently have a dangling commitment.
In this commit, we add a new method AppendRemoteCommitChain. This
method is meant to be used once we extend a new state to the remote
party, but before we actually transmit the CommitSig message. With this
method, we store a fully valid CommitDiff on disk which can be used in
the case that we need to retransmit the state to the party as they
didn’t fully receive it.
In this commit we finalized the structure of the CommitDiff struct by
adding a set of LogUpdates, and also a valid CommitSig message.
The LogUpdate struct houses a messages that were transmitted and
locked-in with the new commitment state. We include the LogIndex along
with the wire messages itself in order to be able to properly
reconstruct the update log upon restart.
The CommitSig message included should be transmitted after the set of
LogUpdates, and fully covers the new commitment state and any new (or
already present) HTLC’s that were included as part of the state.
In this commit, we modify the UpdateCommitment method to accept a full
ChannelCommitment rather than a new transaction, the sig, and a
ChannelDelta. This new structure of this method also takes advantage of
the new bucket structure of the storage schema. Additionally, this
method will now atomically swap in the new passed commitment to point
to the LocalCommitment value within the struct.
In this commit we add a new MarkAsOpen method to the OpenChannel
struct. This method replaces the existing MarkChannelAsOpen method
which targeted the database struct itself.
In this commit we comptely overhaul the existing storage of the
OpenChannel struct to use the new common serialization defined within
the codec.go file. Additionally, we’ve modified the structure of the
channel database on disk. Rather then use the existing prefix based
segmentation, everything is now bucket based. This has resulted in much
simpler and easier to follow code. The bucket progression is:
openChannelBucket -> nodeBucket -> chainBucket -> channelBucket. We add
a chainBucket as it’s possible that in the future we may have several
channels on distinct chains with a given node.
With the above changes, we’re able to delete much of the existing code
within the file, drastically reducing its size.
By adding these two fields, it is now possible to fully reconstruct the
channel’s update log from the set of HTLC’s stored on disk, as we now
properly note both the log index and HTLC index. Prior to this commit
we would simply start the new log index based on the amount of HTLC’s
that were present in the prior state.
In this commit, we restructure the OpenChannel struct to used two
distinct ChannelCommitments: one for the remote party, and one for the
local party. With this, we now partition the local state and the remote
state. Previously, we weren’t properly tracking the state of the remote
party. As a result, there were certain classes of failures we were
unable to properly recover from. With this separation, we can now
handle them, and the OpenChannel struct is slimmer and more
understandable.
In this commit we’ve added a new struct to the package:
ChannelCommitment. This sturct houses all the common data the comprises
a particular commitment state. This will soon replace the open fielded
commitmetn fields within the OpenChannel struct.
In this commit, we add a new files to the channeldb package: codec.go.
This file is similar to the way that serialization is done within the
lnwire package. The goal of this file is to reduce all the duplication
within the common serialization methods across the package.
In this commit htlc channeldb representation have been augmented
with onion blob field, and (de)serialisaion functions have been changed
to make the onion blob persistant.
After addition of the retransmission logic in the channel link, we
should make the onion blobs persistant, the proper way to do this is
include the onion blobs in the payment descriptor rather than storing
them in the distinct struct in the channel link.
In this commit BOLT№2 retranmission logic for the channel link have
been added. Now if channel link have been initialised with the
'SyncState' field than it will send the lnwire.ChannelReestablish
message and will be waiting for receiving the same message from remote
side. Exchange of this message allow both sides understand which
updates they should exchange with each other in order sync their
states.
In order to be able to properly restart switch several times we should
have the sequential process of channel link stop. In other words if we
stopped the switch we should be sure that all channel links have been
stopped too. Addition of the goroutine during the force close was added
because of the deadlock:
Trace:
1. link:force_close_notification
2. link:wipe_channel
3. peer:switch_remove_link
4. switch:stop_link
5. link:wait <-- deadlock
This commit where added as a measure to avoid the panic during several
server simultanoius fault. The panic happened becuase *t.Testing
structure is not concurrent safe.
In this commit the reestablish message have been added, which serves as
channel state synchronization message. Before exchanging the messages
for particular channel peers have to send it to each other as the
first message in order to be sure that non of the updates have been
lost because of the previous disconnect.
In this commit we add a new type to the lnwire package: FundingFlag.
This type will serve as an enum to describe the possible flags that can
be used within the ChannelFlags field in the OpenChannel struct.
We also define the first assigned flag: FFAnnounceChannel, which
indicates if the initiator of the funding flow wishes to announce the
channel to the greater network.
Also includes:
* improved error handling when pruning channels
* more aggressively signals errors when enumerating height outputs
* removes use of variadic functions in Incubate, AwardDiplomas
* renames AwardDiplomas to GraduateKinder
* short circuits channel maturity test after finding 1 non-grad output
* replaces prefixed outputs in height buckets with files, instead of
empty buckets
